Sunscreen compositions are typically categorized as either aqueous or non-aqeuous compositions. Aqueous sunscreen compositions are typically creams formed as emulsions containing the active UV absorbing compounds and additional ingredients such as waterproofing agents, fragrances, emollients and other skin care ingredients. Non-aqueous sunscreen compositions are those that are typically solvent-based compositions that can be formed as gels for topical application or sprayed-on, for example from an alcohol based solution of the ingredients.
In order to keep the emulsion stable in the cream, thickeners are generally utilized. The most common thickeners are formed from cross-linked acrylic acid and are commonly known as carbomers (e.g., Carbomer 940).
While emulsion based sunscreens contain water as the continuous phase, application of these sunscreens to wet skin does not generally pose much of an issue. However, with the advent of continuous spray sunscreens (i.e. ethanol based with very little to no water present), application to wet skin causes the organic UV absorbers to become insoluble in the water/ethanol mix. This phenomenon causes the applied sunscreen to become white (an un-desired aesthetic affect) and may even cause non-uniformity within the film upon drying.
Consequently, application of an emulsion to wet skin leaves the wearer's skin tacky and white until the sunscreen has completely dried. Accordingly, there is a need to provide a sunscreen that overcomes these undesirable effects.